Device for sharpening the rotary circular knives of slicing and other machines



Sept. 1, 1931. c. F. M. VAN BERKEL 1,821,280

DEVICE FOR SHARPENING THE ROTARY CIRCULAR KNIVES OF SLICING AND OTHER MACHINES Filed July 9, 1925 2 Sheets-Sheet 1 P 1931- c. F. M. VAN BERKEL 9 39 DEVICE FOR SHARPENING THE ROTARY CIRCULAR KNIVES OF SLICING AND OTHER MACHINES Filed July 9, 1925 2 Sheets-Sheet 2 element or Patented Sept. 1, 1931 UNITED STATES PA ENT OFFICE I COBNELIS FRANCISCUS MARIA VANB'ERKEL, or wAssEnAAnNnTHEnLANns, ASSIGN'OR To U. s. SLIG'ING- MACHINECOMPANY, OF LA FORTE, INDIANA, A CORPORATION OF INDIANA DEVICE FOR SHARPENING THE ROTARY CIRCULAR xmvnsor SLICING AND OTHE MACHINES Application filed July 9, 1e25, Serial No. 42,553, and in Great Britain July, 9, 1924..

knives of slicing and other machines.

Known sharpening devices comprisea grinding element and an element forremoving the burr caused by grinding, each element being movable axially into and out of engagement with the knife.

A disadvantage of such devices is that the grinding element is removed from the knife after the element for removing the burr, so that after the grinding operation has been finished the knife is never entirely free from burrs.

The object of this invention is to avoid this disadvantage by providing a device of the kind referred to with mechanism whereby the grinding element is now earlier removed from the rotary knife than the burr removing element, thus ensuring that all the burrs have been removed from the knife.

The saidniechanism is'preferably constructed in such a manner that either the grinding element, and subsequently the grinding element and burr removing element, acts on the knife in the first case, or the grinding elementtogether with the burr removing element act on the'knife in the first case after which operations the burr removing element alone acts on the knife, being finally withdrawn therefromr The mechanism may be actuated by a sin gle operating member for effecting the various movements of the burr removing and grinding elements and, preferably, the operating member is adapted to be'rotated in one direction only. I

Said mechanism may comprise two cams located in different planes,each cam acting on a projection or finger, or like member, which, when moved, causes a corresponding axial displacement of the burr removing the grinding element, as'thecase may be. 1

The sharpening devicem'ay also comprise means whereby the sharpening mechanism 'can be locked in a positionthat unauthor ized persons playing or-working with the adjusting handle orcrank cannot, by so do ing, move the elements against the knife,

VII VIII in Fig. 2, the .in different positions;

the locking-action taking place automatically. y

and lowered on its'support, the construction of the device being such that, when it is raised upon its support, both sharpeningelementsare automatically locked, and when lowered on its support said elements are antomatically unlocked. 7

Preferably, the device is combined means whereby when one, or both, of the sharpening elements is, or are, in the sharpening position, said elements are positively held against lifting movement.

The above and other characteristics of the invention will be more fully described with reference to the accompanying drawings, illustrating a constructional form of the inventionby way of example. I

On the drawings Fig. l-is a side elevation, partly tion, of the sharpening device.

Fig. 2 is a front elevation, partly in sec tion, of said device. 1 r 1 Figs. 3, 4, 5 and 6 show various positions of the actuating mechanism. U

Figs. 7 and 8 are sections on the line parts being shown in sec- Referring to thedrawings:

On the upper surface 1 of a support (eg. the knife bearing of a slicing machine) is secured a holder 2 wherein a 'cylindrical sleeve 8, having a flange 4, is clamped by means of a screw *5 passin through two lugs 6 on the holder. The sharpening mechanism is enclosed in a casing 7 provided, at its bottonipart, with a vertical'cylindrical pin 8 projecting into an aperture'in the sleeve 3 and hearing by means of a set screw 9 on thesurface l. A horizontally arranged actuatingshaft 10 is mounted for rotation within the-casing 7, said shaft being adapted to be rotated in one direction only by means of a crankll. The shaft 10 is held against rotation in the other direction by a helical spring 12 secured atone end to the casing andwound tightly round the shaft so that when the latter is rotated so as to wind up the spring by friction between the shaft and spring the latter grips the shaft and prevents its rotation. The crank can occupy four main positions I, II, III, IV, .(Figs. v3 to 6) in each of which it is resiliently locked by means of a spring actuated ball 13 co-operating with corresponding recesses in the wall of-the casing'7. The arrows in Figs. 3 to 6, inclusive, illustrate diagrammatically the direction of rotation of the crank 11 as viewed from the righthand side of Fig. 2. When the crank arm is in its full line position shown in Fig. 2 it is in its main position IV and the cams 29 and 30 are in the positions shown in full lines in Fig. 3. When the crank arm 11 is moved to its main position I of Fig. 4, the shaft" 28 by reason of the gearing 26, 27 of Figs. 1 and 2 moves in an anti-clockwise direct-ion as viewed from the front side of Fig. 2 and ,as viewed in Figs. 3, 4, 5 and 6.

Therefore as the crank arm 11 is moved in aclockwise direction to rts various main positions I, II, III and IV the cams 29 and 30 move anti-clockwise as illustrated iirFigs. 3, 4, 5 and 6.

A grinding stone 14 is located at one side .of the knife with its shaft 45, which is spring controlled, rotatably arranged in a sleeve 46, the latter being'slidably arranged in an outer sleeve 15 having a slot through which an arm 16 projects outwardly, said arm being connected to the sleeve 46 in such a manner that the movement of the arm in the direction of the arrow (Fig. 2) causes the stone 14 to move towards the knife. The sleeve 15 is pivotally connected at 17 to a part of the casing and is provided at 18 with a slot for a screw connection with ,a cross piece 19 of the casing in order-to vary the grinding angle.

The burr removing stone 20 is mounted on a shaft 21 rotatably arranged in a sleeve 47 slidab'le in an outer sleeve 23., an arm 22 projecting through a slot in the sleeve 23, and being connected to the sleeve 47, A spring always tends to force said stone towards the knife.

A disc 25,is mounted on the shaft 10 and is formed with a slot 24, a. spiral toothed wheel 26, engaging a corresponding wheel 27 mounted on a shaft 28. being also mounted on the shaft 10. The shaft 28 is rotatably mounted on the cross piece'19 of the casing and carries a cam 29 at the side of the grinding stone and a cam 30 at the sideof the burr removing stone, said cams being located in different planes and 'co-operating with the arms 16 and 22, respectively.

The actuating shaft 10 may be locked by means of afinger 31 adapted to enter into the slot 24, said finger being mounted on a shaft 32, to which is also'securjed a hook 33, having a recess 34 for co-operating with the bevelled edge35 of the disc, 4. A helical spring 36 tends to disengage the finger 31 from the disc 25. The disc 4 is further provided with two holes 37, 38 adapted to be engaged by a downwardly projecting pin 39 on the casing 7 for locking said casing in one or the other of two positions. The casing is provided at the top with a button 40 by means of which the casing may be lifted and rotated.

The operation of the lows v In the position shown in Fig. 2, the mechanism occupies the inoperative, or neutral, position, in which the crank 11, the cams 29, 30 and the arms 16 and 22 occupy the positions shown in Figs. 2 and 3. For

device is as folthe sake of clearness, the spiral wheels 26 and 27 and their appurtenances have been omitted in Figs. 3 to 6. If the crank 11 is turned to the right a quarter of a revolua tion, see Fig. 4, the cam 29 moves away from thearm 16 and the spring in the sleeve 15 forces the grinding stone 14 towards the knife 41; The stone 14 is rotated by said knife. f

When the knife is sufficiently ground, the crank 11 is turned again through a quarter of a revolution to the right (Fig. 5) in which position the grinding stone 14 continues in action and the burr removing stone 20 comes into operation, in view of the fact that the cam 30 moves away from the arm 22. Thereafter the crank 11 is again turned a quarter of a revolution (Fig. 6) whereas the cam 29 moves back the arm 16 so that the grinding stone 14- is removed from the knife, which latter is then only acted upon by the burr stone 20 removing the burr from the cutting edge 43. Finally, upon completion' of the revolution of the crank 11 the burr removing stone 20 is withdrawn from the knife and the position of the stones shown in Fig. 3 is again attained.

- During all the above manipulations of the crank 11 the bevelled edge 35 of the flange 4 remains in the recess 34 of the hook 33. The casing 7 is lifted by taking hold of and lifting the button 40, the hook 33 and the shaft 32 being partially rotated by reason of the co-operation between the edge 35 and the hook 33. The finger 31 then enters into the slot 24 in the disc 25 and, consequently, a

if the crank 11 does not occupy the right position, lifting of the casing 7 is impossible.

As soon as the casing has been lifted high enough for the pin 39to leave the hole 37, it may be turned through. a quarter of a revolution around the pin 8 until the pin 39 can enter the hole 38, whereupon said c-asingis lowered and is locked by the engagement of the bevelled edge 35 and recess 34. A rotation of the crank 11. by any incompetent person is then harmless to the knife.

Having now particularly described and ascertaii ied the nature of my said invention and in what manner the same isto be performed what I claim is -l. A d'evice for sharpening the'rotary circular knifeof a slicing'm'achine, comprising,

a pair of grinders disposed at opposite sides "of-the knif'eto be sharpened," spr ings for moving said grindersinto contactjwith the opposite sides of said knife respectively, cam members for holding said grinders away erated by said rotary member to permit one of said grinders to engage said knife in advance of the other grinder and upon further operation by said rotary member in the same direction to withdraw said grinders from contact with said knife and to permit the grinder which was last brought into contact with the knife to remain in contact therewith until Withdrawal of the grinder which first engaged the knife.

2. A sharpener for the rotary circular knife of a slicing machine having one edge beveled, comprising a main and a supplemental grinder, the main grinder being arranged to engage the beveled edge of said knife while the supplemental grinder is arranged to engage the opposite edge of said knife, springs for moving said grinders into contact with said knife, cams for moving said grinders away from said knife against the action of said springs, a rotary device for operating said cams, and mechanism for holding said rotary device against reverse rotation, said cams being shaped upon operation of said rotary member to permit the main grinder to enga e the beveled edge of said knife and thereaftertopermit the supplemental grinder to engage the opposite side of said knife and upon further operation by rotation of said rotary member in the same direction to withdraw said main grinder and thereafter withdraw said supplemental grinder.

3. A sharpener for slicing machine knives comprising a pair of grinding elements one for sharpening and the other for removing the burr, means for effecting movement of said grinding elements into and out of operative position relative to a slicing machine knife in a predetermined sequence, there being movement of such moving means in only one direction, and mechanism for preventing reverse movement of said moving neans to compel movement of said sharpening grinding element away from the knife prior to removal of the burr removing element therefrom.

4. A sharpener for slicing machine knives comprising a pair of grinders one for sharpening and the other for removing the burr, means for moving said grinders into and movements.

out-of operative 'position relative to a slicgrinder inadvance of the removal of the burr removing grinder, a rotary member operable' in one direction only for actuating said moving means, and mechanism for preventing reverse rotation of said rotary member during the cycle of operations.

' 5;A sharpener for slicing machine "knives comprising a pair of grinders one for sharpening-and'theother for removing the burr movable-into and out of operative position relative toa knife to be'sharpened, a plurality of cams for controlling thBJIlOVG- merit of said grinders in a predetermined sequence into operative positionand compelliii'g ;the removal of the sharpening 'grinderfin advance of theburr removing grinder, I means movable in one direction only foractuating said cams to effect such predetermined sequence of movements of said grinders, and mechanism for preventing'reverse movement of said cams. f

6'; A -sharpener for rotary slicing machine knives comprising a'grinding element and a burr removing element movable into and out of operative positions relative to arotaryf slicing machine knife'to be sharpened,

mechanism comprising cams for compelling a predetermined sequence of movements of said grinding elements includingremoval of the grinding element in advance of the "burr removing element, and mechanism for a preventing reverse movements of saidcams to maintain] such predetermined sequence of movements of the said grinding elements.

7 A sharpener for slicing machine knives comprising grinding elementand a burr removing element for engaging opposite sides of a' knife to be sharpened, spindleson which said "grinding elements are mounted, means for supporting said spindles for movement"longitudinally thereof to bring said grinding elements'into and-out of engagement with a knife toflbe" sharpened,

mechanism comprising cams for actuating said-spindles to'niovethe grinders relative to said "knife, means for supporting said cams for predetermined sequence ofmovements including 'delay in'i removal of the burr removing element until after'the grinding element has been removed, and'nonreversible-means for moving said cams to secure snch predetermined sequence of 8 A sharpener slicing machine knives comprising a grinder for performing the major, operation, a second-grinder forlrcinoving the burr formed bysaid firstlnamed gi'inder, said grinders being movable into and out'of engagement with'a slicing machine-knife to be sharpenedymeans for coiitrollfingthe movements of said grinders c to compel the's'ame to have a predetermined ableinto and out of engagement at oppo- V sitesides of the knife to be sharpened, rotary cams for controlling the movements of said grinders toward and from said knife,

a single shaft for carrying said cams to compel a predetermined sequence of movements of said grinders including delay in the removal of. theburr removing grinder from the knife until'after the main grinder has been removed, and means for preventing said shaft from beingrotated except in one direction so. as to cause said cams to always move sald grinders through the same predetermined cycle of movements.

10. A sharpener for rotary slicing machine knives comprising a grinding element and a burr removing element, means for 'moving said elements into and out of 0perative positions relative to a rotary slicing machine knife to be sharpened, vmechanism for actuating said moving means, and mechanism for compelling operation of the said moving means to effect removal of the grinding element away from the knife before the burr removing element is removed.

11, A sharpener for rotary slicing machineknives comprising a pair of grinders one for major operation and the other for removing the burr, means for moving said grinders into and out of operative positions relative to a rotary slicing machine knife to be sharpened, and mechanism for compolling a predetermined cycle .of movements of Said grinders while reversal thereof is prevented, such cycle of movements including movementof the major grinder into engagement with the knife followed by the movement of the burr grinder into engagement with the knife and after an interval while bothgrinders are in engagement with .the knife movement of the major grinder away from the knife leaving the burr grinder in engagement therewith for an interval after which upon continued operation the-same cycle must berepeated.

12. -A sharpener for the rotary circular 1 knife of a slicing or other machine, comprising a mam grinder, a supplemental grinder for removlng the burr produced by said 'main grinder,said grinders being movable into. and out of engagement with the opposite sides of the rotary circular knife to be a sharpened, and manually operated :mechanism for controlling the movement of the grinders into engagement with said knife and out of engagement therewith, said mechanism being so constructed and arranged that the main grinder must always be removed from the knife before the burr. removing grinder is removed, the latter being confined upon operation of said manually operated mechanism to remain in engagement with" said knife until after the main grinder has been removed. I

In testimony whereof I .aflix my signature.

CORNELIS FRANCISCUS MARIA vlnBERKEL.

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